Laserfiche WebLink
Workplan for Additional Assessment and Feasibility Testing 3 <br /> 7-Eleven Inc Store No.17334 4501 North Pershing Avenue Stockton CA October 17,2001 <br /> Drilling/Soil Sampling <br /> Drilling will be conducted using a truck-mounted drill rig equipped with 8-inch-diameter hollow-stem augers. <br /> Soil samples will be collected at 5-foot intervals to a total depth of each boring beginning at 5 feet below <br /> grade using a split-spoon sampler lined with 2-inch-diameter by 6-inch-long brass sample tubes. The <br /> hollow-stem augers will be steam-cleaned before drilling, and sampling equipment will be cleaned between <br /> each sampling interval. Each soil sample will be screened for volatile content using a photoionization <br /> detector(PID). Soils encountered during drilling will be logged using the Unified Soil Classification System <br /> by an IT Corporation field geologist,working under the supervision of a California registered geologist. One <br /> sample tube from each sampling interval will be sealed with Teflon sheets, capped,taped, labeled, and <br /> placed on ice in an insulated container. <br /> Selected soil samples from each borehole will be analyzed by a State-certified analytical laboratory for <br /> benzene,toluene, ethylbenzene and xylenes(BTEX),total petroleum hydrocarbons-as-gasoline (TPH-G) <br /> by EPA Method 8020/8015,and oxygenates MTBE,tert-butanol (TBA),diisopropyl ether(DIPE), ethyl-tert- <br /> butyl ether(ETBE), and tert-amylmethyl ether(TAME) by EPA Method 8260. Samples from the capillary <br /> fringe,significant lithologic changes, any areas of elevated PID readings, and total depth of drilling will be <br /> analyzed from the borings. <br /> All soil generated through drilling will be placed in Department of Transportation (DOT)-approved 55-gallon <br /> drums pending characterization and disposal. Water generated by steam cleaning will be temporarily <br /> stored on site in DOT-approved 55-gallon drums pending characterization and disposal. All waste will be <br /> disposed of as non-hazardous at a certified facility by a licensed hauling firm. The vertical delineation <br /> boring will be backfilled to grade after drilling with neat cement and capped at grade to match surrounding <br /> surface. <br /> Vertical Delineation Groundwater Sampling <br /> The Simulprobe or hydropunch device will be used to collect discrete groundwater samples at depths of 30, <br /> 40, and 50 feet below grade to identify vertical concentration changes with depth below grade. The <br /> samples will be collected into 40-milliliter volatile organics analysis(VOA)vials,filled to zero headspace, <br /> acidified and kept on ice until delivery to a state-certified laboratory for analysis. Groundwater samples will <br /> be analyzed for BTEX and TPH-G by EPA Methods 8020/8015 modified, and oxygenates MTBE,TBA, <br /> DIPE, ETBE, and TAME by EPA Method 8260. <br /> 17334SAW.DOC <br />